In known mechanically driven timepieces, the mechanical storage of energy is effected by means of weights or driving springs. Furthermore, mechanical components in the oscillating system determine frequency and effect regulation of running. Purely mechanical timepieces of this kind are relatively simple, inexpensive and of robust construction.
In the course of progress of technology, purely electronic quartz timepieces have been developed in which timing pulses are derived directly from the divided quartz oscillation. In addition, transistorized balance timepieces are known in which direct synchronization of the transistor-driven rotary pendulum is effected by means of the quartz timing pulse. Both these timepiece movements have good accuracy of running, but are relatively elaborate and expensive. Further, they require larger electrical energy storage means for driving the associated timepieces.
Finally, mixed systems including mechanically driven timepieces are known in which pulses of a subdivided reference frequency are transmitted to an electromechanical transducer which acts on a mechanical synchronization device. This direct synchronization with direct action of the pulses on the timepiece has the disadvantage that the attainable range of synchronization is too small for many purposes.